18. Intro to the Immune System Flashcards
Myeloid progenitor cells give rise to…
red cells and phagocytes
Lymphoid progenitor cells give rise to…
B and T lymphocytes
Erythropoietin
production of erythrocytes
Thrombopoietin
development of platelets
GM-CSF (Granulocyte Macrophage Colony Stimulating Factor)
development of leukocytes
RBC
formed by erythropoiesis in the bone marrow
no nucleus
Platelets
form plugs
no nucleus
lifespan = 7-10 days
T cells
CD4+ = helper T cells
CD8+ = cytotoxic T cells
B cells
produce and secrete antibodies
Dendritic Cells
APCs
3 main types:
Langerhans cells (skin)
Interdigitating cells (Lymph node)
Follicular Dendritic Cells (B cell follicle)
Monocyte
kidney-shaped nucleus
become macrophages in the tissues
Macrophage in liver
kupffer cells
Neutrophil
multilobed nucleus
early inflammatory response
granules contain proteases
Eosinophil
kills parasites that cannot be digested
Basophils and Mast cells
Both cells secrete histamine and heparin
Basophils circulate in blood, mast cells don’t
acute inflammatory response
important in allergy and hypersensitivity
NK Cells
kill by inducing lysis and apoptosis
primary lymphoid organs
Thymus and Bone Marrow
Secondary lymphoid organs
The Spleen
Skin
What does the spleen do?
blood ‘filter’ = removes dead RBCs
asplenia
Rare individuals are born without a spleen
Problems with generating antibodies
High susceptibility to bacteremia
Schistosoma mansoni
increased portal pressure and enlargement of the spleen
spleen can rupture leading to death
Mucosal Associated Lymphoid Tissue (MALT)
These tissues include:
The respiratory tract
The gastro-intestinal tract (Peyers patches)
The genito-urinary tract
What % of lymphocytes are lodged in the spleen
25%
Macrophage in brain
microglia
Macrophage in kidney
mesangial cells
Macrophage in bone
osteoclasts
